foo


 
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# 1  
Old 09-24-2008
foo

if [ `echo ${cld}foo|grep $dow` ]; then
echo Its Cold for $sid at $c_dst
$jobroot/scripts/abc.sh $sid COLD $c_dst
elif [ `echo ${hot}foo|grep $dow` ]; then
echo Its Hot for $sid at $h_dst
$jobroot/scripts/abc.sh $sid HOT $h_dst
else
echo No backup for $sid today

wat does foo do ??

Last edited by bn_unx; 09-24-2008 at 04:46 PM.. Reason: ....
# 2  
Old 09-25-2008
It's a lazy coding hack used to prevent a syntax error in the event that $cid or $hot are not defined. The 'foo' part of the string doesn't prevent the match as grep ignores it. That said, it could actually cause it to break if $dow just happens to be "foo" (or some substring of it).
A tidier solution is to instead use "$cid" or to first evaluate "$cid" and check it's defined.
# 3  
Old 09-25-2008
And tidier still to avoid the rat's nest of test backticks echo.

Code:
case $dow in
  $cld) 
    echo Its Cold for $sid at $c_dst
    $jobroot/scripts/abc.sh $sid COLD $c_dst;;
  $hot)
    echo Its Hot for $sid at $h_dst
    $jobroot/scripts/abc.sh $sid HOT $h_dst;;
  *)
    echo No backup for $sid today;;
esac

This assumes some things about how $dow and $cld and $hot are set up; you might need to tweak this if they are not simply one-to-one, but you get the idea. This is IMHO much more readable, as well as more efficient.

If $dow is the numeric day of the week and the values of $cld and $hot are something like 7 (signifying Sunday) and 135 (Mon Wed Fri), then perhaps

Code:
case $cld:$hot in
  *$dow*:*)  echo it's cold;;
  *:*$dow*)  echo it's hot;;
  *) echo it's not;;
esac

 
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